Transistor Identification and Testing made easy.

[@MrCarlsonsLab]

To learn more about electronics in a very different and effective way, check out my Patreon page. Click this link: www.patreon.com/MrCarlsonsLab

[@annetimms8431]

L

[@anwandaedward9609]

Congrats prof

[@roimark358]

How about MOSFETs? In testing/checking MOSFETs using Multimeter, when the gate is charged, why some MOSFETs (N-channel & P-channel), the drain to source let us say 0.002 or less, others, starts with 0.435 and running up as fast as a second or half a second until showing infinite? What does it mean? Does all MOSFETs behave like that?

[@ankomayawoada2663]

An easy way to identify the emmiter from the collector is the emmiter always have a higher resistance then the collector because of the base emmiter junction (bias)

[@qwertykeyboard5901]

Finds 13003 Me: I like this. A lot.

[@antoniosnikolaoy3754]

Good evening from Greece, I have seen a lot of videos on the internet, but yours is all the money, the best explanation I have seen, well done, you are a person who has the natural gift to convey what you know correctly.

[@MrCarlsonsLab]

Thanks for your kind feedback!

[@tunkunrunk]

I've spent one year and a half (since I started self learning electronics) to find the best video on how to test transistors , and I've finally find one , thanks a lot

[@rayhindle642]

If your new to electronics and wish to learn the basics this guy explains transistors in a very easy manner, his teaching method is basic , simple, and therefore puts information across in an easy to understand way.......A must watch video. Ray H. from the U.K.

[@kenzingzong6704]

This is so stupid because I feel stupid lol, I have been working with electronics forever (wall socket christmas light bulb kid, 33 now, but lived through charred hands) and designed circuits with bipolar transistors and so on but for some reason this is one of those goofy things I seemed to skip in my education. I am one of those guys that learned on my own and have an extensive knowledge but sometimes simple things like this remind me the holes in my education. What you have done with this youtube channel has been a huge service to people like us who delved heavily into this but never had that teacher there to really hammer the basics down. In fact some of the stuff you teach on your channel actually reminds us or teaches those who thought they knew this stuff because they simply took the rumors as gospel until you proved otherwise. You sir are a real tech, a real joy to watch, and a teacher. The best kind. Please keep up what you do. Us other folks who thought we knew our stuff are watching and going.. "whoah duh, I should have known that!" In the electronics community you are becoming a real hero and you deserve it :)

[@shadetreetrader1135]

Well said Ken! Couldn't agree with you more. Yet again another great video Mr C.

[@jagitlittlepill5863]

Sir. I started out in electronics watching my father work on television radios of the 20s though to the 70s. This was back when you could go down to your local 7-11 and test you horizontal vertical hold vacuum tubes and if bad there was a box just below the tube tester where you could find one and your back watching television. The smell of solder along with the voices the would call out call signs from the ham radio. This with my dad taking the time to teach me and later pit me though a home corse from The National Radio Institute or as it was called in my day NRI. On color television repair. It was on from that day on. I've since taking on teaching several of my son's friend's the basics that has turned into 25 a year. Kids who don't have much. I don't charge but the faces that light up when they figure it out is priceless. Since I found you videos you have made it so much easier. Thank you sir it's a pleasure having you in my class twice a week. God bless sir. P.S. If you find you have equipment that has past its usefulness for you. Older oscilloscope not vintage just something you don't use are need and would like to pass it on. It would go to a good cause sir. Please don't think me less for asking because if you don't know you may pass up a blessing. Thank you for your time sir.

[@AndrewTa530]

this man is a national treasure to be protected at all costs

[@Bristoll170]

The extra trick to that, is identifying the collector and emitter (of an odd transistor) pins. The reading between the base and emitter is always higher than reading between base & collector. Excellent content Mr Carlson, always enjoy it. Cheers Pete'.

[@RaulHernandez-lg5nw]

I learned this fact of junction readings from emitter -base to base-collector being lower for silicon transistors in the early 1970's. I'm surprised he didn't mention it!

[@jamesaulgur4556]

This guy has my dream job... He is awesome at what he does and explains it very well... I really miss doing electronic trouble shooting even on my own stuff. Who Knows maybe that since I am retiring I can get a shop setup and do some repair on some old radio's and TVs... If you are new to electronics you want to watch this guy.. If you an old salt like me you will want to watch too. Young or old the man makes it fun and exciting. Something that went away from me after almost 20 years when SOC (systems on a chip) technologies came out.. And pretty much made the art of repairing consumer electronics obsolete with the exception of high end audio and ham gear and others a like. I will say that his working with tubes has sparked my passion as in my education in electronics was split between both tube and solid state devices. My last few years was the death of tube taught theory at least at my particular school. I am very envious of your Tektronix equipment. When working for Western Electric back in the 80s I was assigned a 475B for my use and I absolutely loved that unit. Great Job... Love your channel...

[@douggale5962]

It's nice to watch a video that doesn't have "um", "ah", "so on so forth", "and stuff like that" every two seconds. You are well spoken!

[@MrCarlsonsLab]

Thanks Doug!

[@utpalsarma9018]

One of the best tutorial for anyone interested in electronics with an excellent tutor too! Precise and lucidly explained! Thank you so much!

[@alengregorin8366]

You have a really good presence as a teacher. I have ADHD and its easy to focus on you lectures even on the things i don't understand yet. You should teach, but only the ones who want to be thought like private schools and universities.

[@larrylacroixve3oei489]

You should get an award for such good teaching skills. Very easy to follow. Thumbs up for sure

[@MrCarlsonsLab]

+Larry Lacroix Thanks Larry!

[@matthewmathis62]

You just gave him one!

[@BADALICE]

Glad I caught this one, yes. Thank you Mr. Carlson. Shortly after becoming single I was able to pick up my electronics hobby. My line of work gives me access to a great deal of electronic parts. I have a hard time tossing electronics in the trash. I rob as much as I can when I have time. I started looking up parts on line so I could figure out what I have and what I need to build. I discovered KZbin has so much to offer in electronics it's mind blowing. About a year now I have been dumping money into it, and building simple projects. The projects keep getting bigger. I built my power supply. I should have done a video, it's worth looking at features, and appearance. Really nice, better than off the shelf by far. I'm combining circuits. Learning and experimenting, I really enjoy the LED circuits. I have 3 bread boards on my desk right now, each with several LED circuits, diff leds, colors, shields, mini fiber optic bursts, I built an led vu meter which got cannibalized into a duel flasher circuit. blue green red, it works like a led chase strobe combo, and the single red at the peak hits 3 times pap,pap,pap on each run. Everything in my room that has an led indicator, everything, all leds have been changed to blue. At night my desk looks like, Well I have some ideas, and you are just the right person to help me with my questions. I have some other projects going on cabinetry. I will be seeing you at Patreon some time soon. I'm really looking forward to that. This video bumped me up another notch. Thank you.

[@charlesfick729]

You, unlike some other video's, explain things very well. I've been repairing certain things like guitar amps and audio stuff for years without doing actual electronic repair or, just by testing what I knew how to test and looking for burnt components or bad traces etc, bad grounds.... I needed to know how these work and your explanations are excellent. I'm 65 and my wife decided I should take a course at a local college and if I do, I hope they explain things like you do. A friend of mine just explained a couple things to me on reading resistor codes and helped me out with the multiplier part, I was like that's it? I was always terrible with math but logic is how my brain works. Once I looked at things in a different way, I have no problems learning what I could never do before. Thank you for sharing your knowledge!!! I'm certainly in on watching the rest of your video's......

[@MrCarlsonsLab]

You're welcome Charles! Have you checked this out? www.patreon.com/MrCarlsonsLab

[@michaelroc4079]

College is for certification, not for learning, they have no concern for teaching, just testing on what you know.

[@Seiskid]

This transistor testing is so simple, yet so obvious when you think about it. Thanks for sharing a great test technique.

[@anthonyreo5075]

Sir, you just taught me a system of identifying transistors that I was completely unaware of after 35 years servicing home entertainment products! Thank you for your informative and interesting videos!

[@MrCarlsonsLab]

Anthony Reo Glad you are benefiting from the video's Anthony. Thanks for your comment!

[@johncunningham5435]

Very nicely laid out and easy to understand. When you segment and group them in that fashion, troubleshooting takes on a whole new meaning and speeds up the process; bravo once again Mr. Carlson.

[@MrCarlsonsLab]

+John Cunningham Thanks John!

[@RaulHernandez-lg5nw]

If you don't have the pin out data,you can determine the transistor leads to which is the EBC by taking notice of diode voltage across the junction. The Emitter - Base junction will always be slightly higher than the Base - Collector junction in bipolar transistors! This is how I determine the leads, when I need to know quickly. It works many times in circuit for a good transistor. I've used this technique for many years! I hope this helps new technicians working in electronics!

[@kengamble8595]

Once again a big thank you for the info, very helpful ! For years I've taken apart electronic devices and saved pretty much everything and now have a starting point for checking components ! Have to love the Internet and KZbin for getting so much information out to so many people ! 👏👏

[@bluemac1199]

Just like to thank you for clarifying what has been a thorn in my side being new to the game. Especially since I've been working on a few old components that have been making go in circles for a while. You made it clear and to the point and that's one less circle I don't have to travel. Cheers!

[@bayareapianist]

Well done. Thanks. Some additional information. 1N (for dioides), 2N (for transitors) 3N (special device) are American standards. 2S is Japanese and AC is a germanium and BC (like BC 107) is a silicon European/German standards. AD (germanium) and BD (silicon) are power transitors and BU is a high power switching or high voltage (or both like BU208). 2SA (PNP) and 2SB (NPN) are germanium and 2SC silicon transitors. 2SD's are usually silicon power transitors. There is always exceptions. Germanium transitors were used mostly for pocket radios because of lower voltage drop 0.2V vs 0.7 for silicon. However, the are obsolete now. In some designs, germanium transitors can be replaced with silicon ones. As you said, germanium transitor voltage drop can vary very much with the temperature which decreases when temperature increased.

[@Mig2133]

8.24 sec of this video I learned more then weeks of classes. Thank you very much.

[@MrCarlsonsLab]

You're welcome!

[@AllLoudNation365]

Even after 10 years, you haven't changed. Love it ^^

[@jonathanfairchild]

You are a legend. You don't know how stupid I feel that I'd never put 2+2 to see that N correlates to the NEGATIVE lead and P correlates to the POSITIVE lead. I've always sort of known how the N and P types work theoretically. I don't use diodes often so it's always a little fuzzy. I just look up every once in a while how to test transistors when I need it and always forget after I do it. I'm a big fan of making connections like Pnumonic devices to remember stuff. I've watched tutorials on this several times buy yours was by far the the most helpful.

[@MrCarlsonsLab]

Thanks for your kind feedback Jonathan!

[@edvaioli7340]

I firmly believe that KZbin has the potential to redefine the entire concept of education. It seems I have always been a hands-on learner rather than a book learner, and Mr Carlson's Lab videos not only are extremely well done and informative, but they leave me wanting to learn even more. Keep up the great work. One problem that I have not seen addressed, and that I am encountering as I try to restore a vintage transistor amp is the issue of finding the modern equivalent of the old numbering system for the semiconductors. Does anyone know of an online resource that addresses this or has Mr Carlson's Lab already done so and I missed it? Any help is greatly appreciated, Again, Keep up the great work.

[@richardreiter9821]

Amen to that "wanting to learn even more" comment.

[@MrUbiquitousTech]

I third that! Paul's content is excellent and he's an excellent teacher which is a valuable asset to us. Many know _how_ but few can teach. The top of the page at this site has a good part number look up and cross-reference; it was just shown to me and seems very helpful: www.nteinc.com/

[@Erzahler]

+Ed Vaioli: Yes sir, Ed, most definitely! I am also more of a hands-on learner. I suspect most of us are at some point. Book learning is good and important, but that's only 1/3 of the experience. I attended a year of college. The only thing I learned in that year was that I DON'T LIKE COLLEGE! 😁 I went to trade school three times: twice for electronics (the second time was for avionics), and once for aviation. Some book learning, yes, but over 80% of the experience was hands-on learning, which I think is superior. Even a "brainiac" can't argue with those stats! I still have my FAA A&P license, although I am retired now. To be fair, in that year of college, I did learn Fortran '77, but that was about it. And the only reason I still remember and know it was because I was able to put that Fortran '77 to use on the college's Burroughs 6800 mainframe computer (I know, I'm telling my age! 😄 ). Would you believe the college was still using a card reader? And this was in 1983!!

[@DennisMurphey]

I could see showing Mr. Carlson Lectures in class then having a lab that executed his dialog with hands on. It would allow the lesson to sink in and stick so much better. For my tiny brain anyway. Agree 100%

[@SunilAruldas]

@@dancage2446 updated to 2018

[@pepe6666]

mate. this is awesome. instead of blasting the audience with different types of transistors, you actually showed us a system. im gonna remember most of this. :)

[@simonsparks2602]

I comment from time to time, but always a thumbs up on every video. Its just to let you know how we love everything you do.

[@MrCarlsonsLab]

Hey Thanks Simon!

[@Deebz270]

We most certainly do Simon.

[@rafdavfl]

Notwithstanding the "bipolar transistors" issue below, this is a very informative vid to start out learning about semiconductors. I find most of Carlson's lab vids very informative and helpful for the student.

[@jerrypeal653]

I’ve watched this before but just want to say thank you for taking the time to pass on your knowledge.

[@MrCarlsonsLab]

You are very welcome Jerry!

[@DennisMurphey]

Just found this video on Transistors, I have several model train sound boards that seem to fail for no reason, they have transistors on them and i was told that was usually the weak component. now, maybe i can detect the failed part and fix this hard to find sound boards. Thank You Meistro well done again.

[@gaborbanfalvi3917]

I discovered your chanel just a few month ago and i starded to whach your videos and i have to say AWSOME I like the way you explain things. Very clear

[@FireguyNtx]

The best and most simple explanation I have seen, thank you. Most vid's drone on for 20 min. and I still had no idea what the heck was going on. In under 10 min. I now have more knowledge than all combined, great way to teach. Thanks again for doing a great job teaching. I have noticed that your the only one I have ever seen use a curve tracer on testing components, and the visual really seems to drive the explanation home for me. It would be great if you could do a video on curve tracers, how they work, and how to use them. They seem to be a piece of test gear that has been forgotten, or not used much anymore, but seems to fascinate me because they can tell you a lot of information otherwise lost. Just a suggestion. Always love your videos, give a "up", and cant wait to see whats next.

[@xtraceex]

Nice explanation. My electronic heyday was back in the 2Nxxx days, so your explanation of the 2SA / 2SC notations was much appreciated when dealing with current circuitry. Also, don't forget about the catastrophic "collector-to-emitter" short

[@teagarsky1986]

Trying to find info on testing transistors in my vintage 1978 FM receiver, I initially thought I had a Mosfet Transistor, but later when I googled the transistor p/n (2SB595 & 2SD525) I noticed that the terminology of the three terminals on the transistors stated on the datasheet was different than that being used by Mosfet transistors. Mosfets terminals are named: gate drain and source; while Bipolar terminals are named Emitter Collector Base. The datasheet I found also identified that the B595 was a PNP (Emitter, Collector, Base) and the D525 was a NPN (Base, Collector, Emitter) transistor. After watching a ton of videos on transistors, I found your video to be the best one for my application, and that my transistors were good, your video was very helpful, and well done.

[@MrCarlsonsLab]

+Teagar Sky Glad the video helped, thanks for your comment!

[@raross6119]

Nobody was really using mosfet in 78 more than likely transistor

[@kennethiman2691]

Thank you for these shorter, practical videos.

[@southjerseysound7340]

I really like your way of testing.Granted its not 100% but its a great way for 99.9% or us to get to where we need to be.

[@sandornagy5954]

Wow... with one diagram you have cleared up my misunderstanding of the difference between NPN and PNP ... thank you. Awesome vids.

[@6F6G]

Nice tutorial but a note on the 2S transistor system. You might think a transistor marked C144 is a 2SC144 but its not. It really is a DTC144 which is a silicon transistor with a built in resistor in series with the base intended for digital switching purposes. If you didn't know this then testing it as a normal transistor would make you think it was faulty.

[@sssttt6533]

+bob s good comment

[@michaelhawthorne8696]

+bob s That's a useful device to keep in mind, thanks

[@emerituse3390]

True! There's a number of them. C104, C114, ect. All with varying base resistor values. I believe they come in A (PNP) values as well. I love them. They're especially nice when building transistor switching circuits in tight places. :)

[@Deebz270]

Wow, synchronicity in action. Literally 5 hours ago, I was researching a component (a SOT23-6 packaged device of some sort ... ) and in so doing read a whole lot about 'digital transistors (with the resistor on the base...). You Bobs, have just filled in a tad more knowledge. Thanks for that Dude. . This is why I love Mr Carlson's Lab so much, the YT community here on Paul's channel really works well, a rarity on YT.

[@technixbul]

also as far as i know A124, A133, A144 and C124, C133 who are DTA and DTC where A means PNP and C means NPN and the difference is in internal resistor values

[@shamsheralamraja]

Extreamly well done. wish you were my physics teacher about 45 years ago, oh wait we did not have to-92 back then. Great job. Thanks and keep it up.

[@MrCarlsonsLab]

+Sam Raja I guess I will have to do a video on tube Identification too :^) Thanks for the kind comment Sam, glad your enjoying the video's!

[@lwilton]

Nice video, thanks. I've been using a diode checker (or more commonly a VOM) for preliminary transistor checking for about 50 years now. But then I grew up in the TO-5 and TO-92 era. In that case the basing was usually EBC clockwise, looking at the bottom of the can with the leads at 12, 3, and 6 o'clock positions. Early TO-92 packages also had the same pinout, before they went to putting all three leads in a plane.

[@gooseknack]

Thank you Mr Carlson.. you have just cleared up around 40 years of mystery surrounding transistors...lol Nothing I have ever read, followed, watched(and built from) has ever explained transistors in such a simple way. The moment you said "positive", the penny dropped on the NPN/PNP meaning.. With the numbering/clasification system, no one speaks of it, even a book I read some years ago called "transistor identification", go figure! I only remember one book by Forrest Mimms that briefly demonstrated transistor testing and identification, it wasn't 100 percent clear. It is now... Imagine the facepalm moment I had at thinking back through the years to the age of five, when my electronics interest kicked off.. thinking of all those years of not understanding transistors and how stupid I feel today! 🤣

[@MrCarlsonsLab]

Glad this was of benefit Brett!

[@vancedewitt336]

I have to pause right here at 2:45, drop down here and thank you, You know how much time you just saved me, looking things up,? Yes I"m sure you do. Thank you very much; knowing the codes makes a huge difference. Thank you. Seriously. Oh yes, I subscribed, I have seen a few of your videos now, and I like your presentations, you make it enjoyable like it should be, clear and simple, and electronics is easily enjoyable., no end to what you can do,. Fun stuff, I'd like to see what you work on for yourself, all the cool stuff you build. I'll be here.

[@joaquinaguirre2976]

Thank you Mr. Carlson. I am getting a lot of knowledge from your work. I really appreciated.!

[@bernardjones6162]

What a great teacher you are Mr. Carlson! Thank you!

[@MrCarlsonsLab]

+Bernard Jones Thanks Bernard!

[@rsattahip]

Seriously, why did they have to change the locations of the E-B-C? It made so much more sense for it to be in the middle. Thank you, enjoy your brilliance.

[@Roflcopter4b]

The two standards were developed simultaneously in America and Japan respectively. There wasn't any change, they just did it differently.

[@abeleballestri612]

Mr Carlson that was the best explanation l have ever seen how to test transistors pop and non .thank you very much for your excellent didactical explanation for everybody interested in transistor science. A. Ballestri Switzerland .

[@yurimodin7333]

VERY nice and SIMPLE explanation. You really broke it down well into layman's terms. GOOD JOB!

[@MrCarlsonsLab]

+mark holstrum Thanks Mark!

[@larryclark9380]

Thanks again. I have been taking the US Navy Electrical and Electronics Training Series (NEETS)-which is free online by the way. Module #7 covers solid state devices such as these transistors. All of the training can be downloaded as a PDF. As I get bogged down reading and studying, I go on to KZbin and get additional help to spice it up. Your channel has really helped inspire. I now have a transistor tester and an old Navy usable oscilloscope that I picked up on e-bay on the cheap. Electronics hasn't been my background really in the past but I am really finding this stuff way cool and my focus is now locked on it. KZbin university is much better than the college hacks who exist to siphon bank accounts. God bless!

[@MrCarlsonsLab]

That's great to read Larry! Glad the channel is helping you.

[@Damaraja]

You’re the best, Mr. C. I hope you know how much we appreciate your work. Most generous, helpful, and fun! All the best to you, sir ✌️🎛🤙

[@MrCarlsonsLab]

Thanks for your kind comment, and feedback too!

[@stefanvojvodic8274]

This video is a great one. I like how you explained everything about transistor naming and testing. It helped me a lot. Thank you. :)

[@michaelhawthorne8696]

Nice video again there Paul, straight to the point and I now know that certain letters point to NPN or PNP, That should help quite a lot thank you. As an addition to your video may I say that if you have a transistor with damaged markings and therefore can't look up the data sheet but you want to know which is the Collector or the Emitter having got the two diode readings as you have demonstrated, then if you're careful and allow the DMM to settle on the readings, then the Emitter should be the larger of the two readings.

[@MrCarlsonsLab]

+Michael Hawthorne Thanks for your input Michael! Glad you enjoyed the video.

[@skfn]

Pure concentrated knowledge! Thanks

[@cassvirgillo3395]

Hi Mr. Carlson, Your scary good. So glad to be a sub. Between you, All American Five Radio, Mr. Richard McWhorter, Uncle Doug and a few others, I am really learning a lot about electronics and glad for it, Thankyou for sharing your vast knowledge of the subject and I refer you in my comments to other electrically inclined KZbinr's. Awesome channel. Take care, be good, C.

[@Satchmoeddie]

Have you seen any "TRX Bench" vids yet? Peter is another good tech.

[@cassvirgillo3395]

Seth B Hi Seth, Can't say as I have. I will check him out. Thanks, Happy 4th, C.

[@erichernandez5659]

Dude that was the best explanation of a trans yet I have seen. Thanks

[@MrCarlsonsLab]

You're welcome Eric!

[@vancedewitt336]

I went to your link, suddenly I was right inside your lab, as the home page opened across eyefinity triple screen,: boom I'm sitting right where you sit in a full size lab. It was amazing., really nice equipment. I'm in your lab looking at it actual size; virtually. I was not expecting that , I think I saw some videos from there. You have some really good offers there, very reasonable, Thanks, GTK very handy.

[@wendywhales2310]

Very,Very good explanation of how to check the two types,made my day.Now it has been thoroughly simplified,Thank You.

[@MrCarlsonsLab]

You're welcome Wendy!

[@joemazza1011]

Wow thank you this video was very helpful I've been trying to learn vintage electronics so watching this was very helpful specially for testing solid-state transistors

[@MrCarlsonsLab]

You're welcome!

[@joemazza1011]

Mr. Carlson wanted to ask you a question about a domino capacitor that is in this radio that I am trying to fix I am pretty sure they're bad it's a domino capacitor from the 60s when I go to look up the color code I'm really having a tough time figuring out what the correct value is it's either 10 picofarad or 40. It is a red diamond shape it also looks like it melted overtime but the color code is gold silver green yellow black black maybe you might be able to tell me what the value is on that I think it's a Micah. I would appreciate it like I said I'm just having a tough time trying to figure out the value and I rather ask somebody that is an expert at it. thank you Joe

[@seanregan730]

I know that there's been lots of vids online about transistors but this is simple and informative. thanks for sharing. I do have a request though. Over the years various transistors have been taken out of manufacture and it would make a great topic showing how to select a replacement transistor from currently manufactured stock. 2SC1969 etc is an example if I recall is no longer available very easily. I'm sure there's many like me who once they start staring at endless data sheets the head starts to fog over and get lost in endless comparisons. Thanks again for the videos and keep them coming best regards Sean in the UK

[@MrCarlsonsLab]

Sean Regan Thanks for your comments and suggestions Sean!

[@royelectrotechnic8711]

Thanks you so much again mr Paul for giving us a clearly information with transistors and how to identify that thing's..

[@MrCarlsonsLab]

You're welcome Roy!

[@asressaraia2340]

Excellent presentation. Concise-to the point and clear. Thanks Asress

[@sonofeloah]

It is a good thing that you mention the testing characteristics for germanium vs silicon transistors. Especially as new generation germanium transistors and ICs are making a comeback in the electronics world again.

[@MrCarlsonsLab]

Thanks for your comment!

[@jl7986]

Hey Mr Carlson's Lab I wish there was a better way I could express my gratitude for your concise and clear-cut explanation of this matter. It's really cleared up the confusion I came across with some of the transistors I've been testing over the past couple days. Thank you for sharing this information, and thank you for sharing it for free. Sub'd!

[@MrCarlsonsLab]

jl7986 Thanks for the nice comment, and sub too! Glad your enjoying the video's.

[@shana_dmr]

Thank you for great video! Even with "a bit" of practice I tend to reinvent the wheel every time I meet unknown transistor, try all the directions and scratch my head until I've figured it out (or in some cases just consult the uncle Internet if part name is easily readable). Having some methodology will certainly help me out:)

[@MrCarlsonsLab]

+kroplaaaa Glad you enjoyed the video!

[@gus_siles]

I recently discovered your channel.. impressive job Mr. Carlson!

[@MrCarlsonsLab]

Thanks Gustavo!

[@LarryDeSilva64]

Always great explanations clear and concise. thanks for sharing Paul.

[@MauroSedrani]

Simple and effective! Thanks Paul!

[@MrCarlsonsLab]

Your welcome Mauro!

[@techwizpc4484]

How do you identify the pins if it has no label.

[@uncontrollabledogs3791]

Great explanation of the difference in identification of transistors. Wish I found this video earlier. So used to the jedec 1 2 3n system. Really tedious looking up components in a thick substitution book in the pre- internet days. Great vid here👍

[@kaypolo]

Thank You for this video. I've been needing to see this for years.

[@MrCarlsonsLab]

No Problem James!

[@Hopeless_and_Forlorn]

Great stuff as usual. I have found that I don't need to know if a transistor is NPN or PNP or even which transistor lead is which before testing. I put one meter lead on one transistor lead and check for appropriate forward voltage when touching the second meter lead to each of the other transistor leads. If that doesn't work, I move the first meter lead to another transistor lead and try again. When I get the correct indications, I have a good NPN bijunction if the red meter lead is on the common transistor lead, and a good NPN if the black meter lead is on the common transistor lead. One caution: if you use an analog VOM set on R X 10 or R X 100 to test diodes or transistors, be aware that there is such a thing as a VOM which connects reversed polarity to the meter leads *in resistance mode only*: red lead is negative, black lead is positive. Question: I have never tried to test a FET using meter diode test function, as I assumed that it would only work with bijunctions. Is it possible, and what are the indications?

[@noelguerrero2770]

There was a time down here when 2Ns were not readily available and we used 2S Japanese made components. Up to this time I thought the 2S system was developed and used exclusively by the Japanese.

[@radiotec76]

Thanks for that explanation. I always wondered why Japanese transistors used 2S.

[@Drekkag]

great one for transistors. makes it alot easier than depending on google all the time since i would have to swivel around and move acros the room. thanks and keep em coming.

[@MrCarlsonsLab]

Glad this helped Adam!

[@JWH-n3v]

Best video on this subject I have come across!

[@MrCarlsonsLab]

Thanks Jerry!

[@stevenhardy2898]

As a component level module repair guy 40 years ago (yep ,transistors were around) let me add to the education. Check between all THREE legs. I have seen where there was a short between emmiter and collector with nothing obvious wrong on the other two legs....especially on metal case transistors as was the 2n3055 used in power supplies. If you say it cant happen.....well you have never encountered "metal dendrites.. Regarding checking in circuit. GET or build an octopus tester and use with your scope or find an sencore sc301 that has one built in. You will cut your probing in half and not deal with the meter latency and get a much better visual picture of the electrical characteristics. Another great usefulness of the octopus tester is when you have a known good board to compare components against that are IN circuit. Instead of a simple go -no go approach ,you can start to differentiate components that are connected to capacitance while in circuit and essentially develop a visual dictionary of how a particular circuit should respond to a small ac waveform. There are useful youtube videos on Octupus testers ...some times called circuit tracters or component analysers.. To give you an idea of how effective and easier it made my job I'll tell you of one module I used to repair regularly. It was a capstan final drive board in a tape drive. A common failure for the board was to inadvertently be directed to go capstan forward and capstan reverse at the same time.Very destructive to the drive circuitry. :-) In just a minute or two I could check two transistors and two series diodes,in circuit ....acuurately and quickly and test them in the machine afterwards. As a challenge one day, I repaired and tested 50 of them on an 8 hour shift and they passed QC the next day. Not bragging ,just trying to illustrate how useful a circuit tracer can be ,especially in a pure analog circuit.

[@MrCarlsonsLab]

Have you looked at my video's list? Just go to my main page on KZbin and click video's, you may find some interesting video's relating to what you mention.

[@stevenhardy2898]

Will do...just started watching your video's......which by the way I wish had been around 50 some years ago when at 11 years old I decided I wanted to be an electronic technician. I remember the kids in the neighborhood being amazed when I hooked an audio recorder up to a tv ,then played a crude tv playback. Don't remember how I did it.....but eventually became a tech in the computer field. I see that electronics is a passion of yours...keep up the good work. It would be a cool thing if many of your videos were available on DVD for sale to potential electronic students.....(something to think about if youtube keeps declining) As you may imagine ,I have had many instructors ,teachers ,and professors over the last 45 years or so. Your are definitely among the top three. You are detailed,know the subject and a good communicator AND I don't have to put the playback on 75 percent speed to understand what your saying. lol

[@jeffreydeutsch7336]

I think you skipped one very essential point. Bipolar transistors often short out collector to emitter. The BC and BE diode tests still check good. This is where the two diode description falls down. I find this to be the most common faulure. You really cannot omit this point even for the most rudimentary testing.

[@SteveMasonCanada]

Very good point. I came here to say that myself. Especially power transistors (TO220, TO3) they often short C-E.

[@artboelke5721]

I was wondering that as well for I will check in circuit emitter to collector for short and quick determination what may be at fault. I do realize it may show a value due to being in a circuit but when using this to check one bad channel in a two channel stereo I have a good piece to compare. Note: I am self taught and only repair my own stuff but that is why I love these great videos to learn

[@jeffreydeutsch7336]

In circuit can make the reading artificially low but not high. If C to E is the same couple of ohms both ways, i would have a closer look. Especially audio amplifier output transistors. If it is bad I would have a look at the driver transistor that feeds it and any fractional ohm (.22,.33 or .47 ohm) resistors in the output circuit. A failure often takes out a few components

[@stevenhardy2898]

yes...see my post on octopus testers and how handy it can be to have a known good board to work with.

[@ianmacdonald6350]

Also beware the double diode packages that look and read like a transistor on a diode test. Seen a few amusing scenarios trying to get some current gain out of one. ;)

[@rickr7333]

Nice tutorial, this is what I used for years troubleshooting failed electronics. You did forget one failure mode that can be detected with a diode tester, collector to emitter punch-though. While it is rare to find a unusual reading from the collector to emitter junction without finding a bad reading from the base to either the collector or emitter, I have found them multiple times over the years and that failure mode usually has pointed to a power supply spike that has punched a carbon trace through from the collector to the emitter. When that happens the base to emitter and base to collector readings can be very normal.

[@MrCarlsonsLab]

+Rick R Thanks for your comment Rick!

[@mohammedansari7888]

this channel deserve a billions subscribers........

[@MrDoneboy]

Excellent video. Thanks for jogging my memory!

[@donlunn792]

Hi Paul first time seeing this vid.Great as always! I have actually taken notes on this. For future reference. Many “Many “ years ago, my Dad said! forget being a Car mechanic.Get an apprenticeship in Radio and TV engineering.Hell Electronics ? It’s the future.And I was offered an Apprenticeship in Radio Tv . But!! Guess which I chose ? Boy was I wrong! “if your looking down Dad! I’m sorry. Now? I’m a Patreon sub.to your site,And also KZbin. Love the vids Paul. Best on the internet. 👍

[@CT1ELP]

Can you believe that you can get a degree in engineering and they never teach you this ! it is the kind of things you have to look for and learn for yourself. Thanks !

[@MrCarlsonsLab]

+CT1ELP Glad you enjoyed the video!

[@BornAgain717]

Best video on subject hands down!

[@jaycronen]

Very informative as usual, thank you very much!

[@santospoland]

This is an excellent video. Thank you VERY much!

[@skippyi6969]

167 thumbs down ? Who the fuck would give this a thumbs down ? Clearly people that hate to learn.....Thanks Paul for all your videos. I have learned how ignorant I really am..

[@MrShobar]

In my old Zenith transistor radios (> 50 yrs. old), the transistors are positioned in removable sockets. I've never had one fail, even though they were prone to failure due to "tin whiskering". I seem to recall that they were Ge devices.

[@MrDoneboy]

Thanks for making since of this, as usual, Paul.

[@MrDoneboy]

I meant SENSE, of course! LOL

[@SABIRALI-gf3fv]

A very helpful video, Thank you, Mr.Paul.

[@MrCarlsonsLab]

You're welcome!

[@kennybassarath7168]

Good job sir. Always refreshing seeing one of your videos.

[@dwtees]

Terrific job. Thanks for taking your time and sharing your knowlege. Again very clear explanations.

[@MrCarlsonsLab]

+Douglas Tees Glad you enjoyed Douglas!

[@willrobbinson]

PS the base / collector forward bias voltage is usually a fraction less than base / emitter bias (helps to confirm config)

[@Spark-Hole]

Noooo! It is about the same.

[@extremelocura]

this is so informative. if you could add a troubleshooting example of a good and bad Transistor at the end that might help even more people like me that are starting out.. Thank you for the video..

[@chuckbear1961]

I`m getting into tinkering with transistors and using them for ignitions ,and switches on home made solenoid motors,,,, Love your bedroom eyes

[@MrShobar]

What frustrates me is when manufacturers of electronic equipment eradicate identifying numbers, or add their own (unobtainable) part number. Great job as always, my friend.

[@MrCarlsonsLab]

+MrShobar Your welcome!

[@thomaslau8806]

Awesome explanation!! You deserve more subs and views!

[@markianclark9645]

yup..i agree with everyone else - great tutorial..very professional..+ les johnson - mr carlson must be a lecturer..we need more like this standard..stuff explained clearly for non techies..thanks

[@MrCarlsonsLab]

+Mark Clark Thanks for the kind comment Mark!

[@jawnjw]

Thank you for teaching us electronic for free.

[@shvideo1]

What a great educational video. Great information. Thank you for sharing.

[@ianbanhamamprepair9457]

Best explanation and test procedure , thank you.

[@theduder2617]

This channel should be financially backed by order of federal law. lol The only thing better than education, is education available to all who seek it. Thank you BIG TIME for keeping it simple. That alone can make it easier for others to become interested in electronics. Which opens more doors of life for them. My love for the electronic world drove me to love the quantum world. Thank you for sharing! By the way, if anyone out there is color blind, do not fear. You too can excel in electronics. I know that first hand. Until people are born meter blind, there will always be a solution for not being able to read color codes such as wires, resistors, and capacitors. I mentioned that because I was told as a teen that I could never repair electronic devices because I could see no color. 25 years of proving them wrong so far. lol

[@MrCarlsonsLab]

Glad your enjoying the videos!

[@mike-yp1uk]

great video thats the kind of stuff that helps us beginners and troubleshooting. thanks jeff for your tip too.